U.S. Pat. No. 7,080,761 describes an example of such a spraying device, wherein the product to be sprayed must follow a complex and narrow path between the conduit for channeling and the output conduit, in such a way that this type of spraying device can possibly operate for spraying a liquid product, but not for spraying a powdery product.
In addition, the form of the output conduit disclosed in this document is also not suited for the spraying of powdery product.
Finally, the air nozzle of this document has a form that is entirely not suited for the effective carrying out of a vacuum capable of sucking the product to be sprayed.